<!-- @format -->

<!DOCTYPE html>
<html>
  <head>
    <style>
      * {
        margin: 0;
      }
      body {
        box-sizing: border-box;
        height: 2000px;
        background-color: rgb(240, 135, 135);
      }
      header {
        height: 100px;
        background: rgb(97, 197, 255);
        position: fixed;
        top: 10;
        width: 100%;
        z-index: -1;
      }
      main {
        top: 100px;
        height: 1700px;
        position: relative;
        background-color: rgb(65, 245, 176);
        z-index: 10;
      }
    </style>
  </head>
  <body>
    <header>1</header>
    <main>2</main>
  </body>
</html>
